What is class polychetae - marine worms, Biology

Assignment Help:

What is Class Polychetae - Marine Worms?

The polychaetes differ from the oligochaetes in several ways. The name itself suggests one of the differences. The prefix "poly" means "many," as opposed to "oligo," meaning "few." Thus, the polychaetes have many hair-like bristles. They also have paired appendages called parapodia that bear the numerous setae. Parapodia have several functions, including helping the worms swim or crawl, as well as providing an anchoring mechanism. Parapodia, in addition, provide increased surface area for gas exchange. Most polychaetes live in marine habitats, and they can be found either living as plankton, crawling on the sea floor, or living in tubes, which the worms secrete around themselves.

Polychaetes also differ from the other two groups in that their anterior is better developed. They have a definite head region with sensory apparatus that include light-sensitive eyes.

 

 


Related Discussions:- What is class polychetae - marine worms

26 The human impact on the environment, 4 Put the following events in the m...

4 Put the following events in the most probable order. (a) Predatory birds poisoned by insecticide. (b) Trees sprayed with insecticide. (c) Earthworms eat leaves which f

Valve replacement, Valve Replacement Replacement of the diseased valve...

Valve Replacement Replacement of the diseased valve is done. This is done biologic tissue valves or mechanical valves. Three types of biologic tissue valves are used. Aut

Assessment of ventricular septal defect, Assessment   On assessment a c...

Assessment   On assessment a child with ventricular septal defect will show clinical manifestations depending upon the size of  the defect. The small defects are usually asympt

Nutrition, Nutrition As we have said earlier all animals are heterotro...

Nutrition As we have said earlier all animals are heterotrophs and require food from the environment. What is this food made up of? If the food of a number of different animal

Preparation of cardiac surgery, Preparation on the Previous Day of Operatio...

Preparation on the Previous Day of Operation Remove all the jewellery, nail polish, cut nails.  The patient's body is cleaned - shaving from chin to toe, inclu

Subcutaneous nodules, These are found in about 3-6 per cent of cases of ARF...

These are found in about 3-6 per cent of cases of ARF. These nodules are typically subcutaneous, firm, painless, freely movable (0.5-2 cm size) and their presence indicates that t

Injury resulting from an accident, Injury Resulting From an Accident ...

Injury Resulting From an Accident Accident was described earlier which meant that accident was a sudden event. However, several legal opinions favored exclusion of suddenness

What are the four groups of protozoans, Q. What are the four groups of prot...

Q. What are the four groups of protozoans? The four main groups of protozoans are the mastigophores flagellated, like the trypanosome that causes Chagas' disease, the sarcodine

How to alternately donating and accepting ions, Select all that are true or...

Select all that are true or correct regarding a buffer: alternately donating and accepting ions a set of chemicals that work together to resist pH change often a weak acid or base

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd